how to drain water heater

I having a new electric water heater being delivered this week and I need to disconnect and drain my current one. I have read a lot of conflicting info on draining the water heater which is confusing. This is what I finally settled on:

1. Shutoff power to WH and turn off cold water.
2. Connect hose to drainage valve at bottom of WH.
3. Turn on hot water tap of any sink (to prevent vacuum in the line).
4. Open drainage valve.

Is this OK?

One last question: Around the perimeter of my basement there is a 2 inch gap between the wall and the floor that looks to be 2-3 inches deep with small rocks in it. Is it okay to drain the WH into this? It's a 50 gallon unit.

If the WH hasn't been drained and flushed regularly (and very few get this treatment), there is a pretty good chance that the drain valve will clog up with sediment and prevent the tank from draining, esp if you have hard water.

If this happens, you can take the valve out altogether, but then water will just flood out of the hole where the valve was -